A cosmonaut is orbiting the earth in a spacecraft at an altitude h =630km with a speed of `8kms^(-2)`. If the radius of the earth is 6400km, the acceleration of the cosmonaut is

Options

A. `9.10ms^(-2)`
B. `9.80ms^(-2)`
C. `10.0ms^(-2)`
D. `9.88ms^(-2)`

Answer

A

Explanation

Given ,`v=8kms^(-1)=8000ms^(-1)`
`r=(6400+630)km=(6400+630)xx1000m`
Acceleration of the cosmonaut a =`v^2/r`
`=(8000)^2/((6400+630)+1000)=9.10ms^(-2)`